The GNU SETL Om gives a brief overview of SETL and GNU SETL, and a few words on what inspired the World's Most Wonderful Programming Language in the first place. It also gives links to the other manuals, and to various external SETL resources.
The setl command and relatives are partly self-describing through the --help and --version options. For full details, please see the GNU SETL User Guide.
The main GNU SETL guide currently is the GNU SETL Library Reference, which describes all the built-in operators and functions.
The PDF versions of the manuals are meant for downloading and unpacking into a new folder, whereupon the cross-reference links among them allow easy local navigation with a PDF reader.
The latest GNU SETL releases, including documentation, are at the GNU SETL web site.
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